In a two-way communication system, and particularly in a two-way messaging system, it is possible during periods of high system traffic for a message to be delayed too long for the message to be delivered to a subscriber unit on the move. The reason is due to the fact that such systems preferably must locate the subscriber unit and then transmit the message in an appropriate region of the coverage area, the appropriate region being a portion of the coverage area in which the subscriber unit was located. Such regional transmission advantageously allows frequency reuse for improved radio frequency spectrum efficiency. If the subscriber unit is moving rapidly, however, then system traffic delays can allow the subscriber unit to move out of the appropriate region before a message scheduled for transmission to the subscriber unit is sent, thereby causing the message to be missed.
Thus what is needed is a method and apparatus for prioritizing the communication of the messages such that a subscriber unit having a high mobility will be more likely to receive its scheduled messages before moving out of the region in which the subscriber unit was located by the system.